Evaluation of the Benefits of Reflectorized Sign Posts to Drivers

Abstract

In United States Federal Highway Administration (FHWA) provides departments of transportation (DOTs) the option of using retroreflective material on sign posts when the DOTs determine that there is a need to draw attention to the sign, especially at night. The State of Ohio Department of Transportation (ODOT) required all Stop, Yield, Do Not Enter, and Wrong Way sign posts to be reflectorized with RED reflective sheeting material and all Chevron, Stop Ahead, and One/Two Large Directional Arrow sign posts to be reflectorized with YELLOW (sign background color) reflective sheeting material as part of ODOT Comprehensive Highway Safety Plan and FHWA' recommendations.In this study, a photometric analysis and a human factors analysis were conducted to estimate the benefits of reflectorized sign posts to driver visual perception, driver guidance and driver comprehension. The study showed that the reflectorized sign posts improve detection, recognition, and comprehension of traffic signs for drivers, especially in nighttime driving conditions.

Keywords

• Traffic sign, Reflectivity, Human factors, Photometric analysis.

Trafik İşareti Direklerinde Kullanılan Reflektif Malzemelerin Sürücüler için Faydalarının İncelenmesi

Abstract

Amerika Birleşik Devletleri Federal Karayolları İdaresi, trafik işaretlerinin özellikle gece görülebilirliğini artırmak ve dikkat çekmek için trafik işareti direklerinde reflektif malzemelerin kullanılabilceğini belirtmektedir. Bu öneri doğrultusunda Ohio Eyaleti Ulaştırma Bölümü karayolları güvenliğini artırmak için tüm Dur, Yol Ver, Girilmez ve Yanlış Yön trafik işareti direklerinin kırmızı reflektif malzeme ile kaplanmasına ve tüm ok işaretli yön levhalarının gövdelerinin ise sarı reflektif malzeme ile kaplanmasına karar vermiştir.Bu çalışmada, trafik işareti direklerinde kullanılan reflektif malzemelerin fotometrik analizi ve insan faktörleri analizi yapılmıştır. Bu analizler sonucunda trafik işareti direklerinde reflektif malzeme kullanımının sürücülerin trafik işaretlerini algılamasına, tanımasına ve anlamasına olan faydaları incelenmiştir. Çalışma sonucunda reflektörlü işaret direkleri, özellikle gece sürüş koşullarında, sürücülerin trafik işaretlerini algılamasına, tanımasına ve anlamasına faydasının olduğu görülmüştür.

Keywords

• Trafik işaretleri, Reflektivite, İnsan faktörleri, Fotometrik analiz.

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